From Longman Dictionary of Contemporary Englishsenile dementiaˌsenile deˈmentia noun [uncountable] MIa serious medical condition that affects the minds of some old people, and makes them confused and behave in a strange way
Examples from the Corpus
senile dementia• I've heard there's a link between this condition and senile dementia.• In this sense the world would be a better place without mental retardation, madness, and senile dementia.• Mr Allsopp was known to suffer from senile dementia and was often seen walking in the area.• Most studies have investigated senile dementia in relatively small populations.• Alzheimer's Disease was now widely known and recognised as an incurable form of senile dementia.• Maybe he was suffering from premature senile dementia?• The main gap was in provision for elderly people with senile dementia and for the new long-stay population. 